I agree that it is best that we avoid posts that are triggering to us. That doesn't necessarily mean we don't care for the poster, but we have to look after our own psychological health.
My mother was still upset way into old age about how her parents treated her. We just don't know all the circumstances often times and for whatever reasons the person just doesn't feel like/isn't psychologically able to tell us all the details.
I have to say it's validating for me to hear other people talk about how my mother was difficult to deal with. (She died a year ago at age 90.)